HOUSTON -- Texas legislators have used credit cards to charge more than $1 million in political expenses since January 2005 but failed to disclose which vendors they bought from, a new analysis shows.

A Houston Chronicle review of ethics commission records between Jan. 1, 2005, and June 30 found dozens of legislators failing to comply with a 1981 law that requires disclosure of all political expenses.

The Chronicle found that Sen. Carlos Uresti, D-San Antonio, had the most undisclosed credit card charges, with $88,000 in payments detailed only with phrases such as “campaign expenses” or “charges for swearing-in ceremony.”

Uresti defeated Sen. Frank Madla in the Democratic primary last year in part by attacking his lavish campaign spending.

Uresti said his reporting shortcomings arose from a fast-paced political year in which he was charging campaign expenses to his credit card and then raising the money to pay for them. He said he is going through his expenses now to file amended reports.

“It’s a tedious task,” he said. “It’s not like we’re trying to hide anything.”

In the past year, the Texas Ethics Commission has fined only three legislators for failing to properly disclose credit card expenses charged to their campaigns, the newspaper reported.

Because the ethics commission audits candidates only when it gets a sworn complaint, most lawmakers have gotten a pass on how they report their credit card spending, the Chronicle found.

The commission’s disciplinary actions and related advisories sent to candidates have prompted some—such as Rep. Rick Noriega, D-Houston, who had more than $19,000 in unspecified charges—to amend reports to disclose details.

Since 1981, state law has required politicians to make full financial disclosure of political expenses. When the ethics commission was created in 1991, one of the first things it did was adopt a rule that said: “A report of a political expenditure by credit card must identify the vendor who receives payment from the card company.”

When a politician creates a political committee, the treasurer receives a two-page letter from the ethics commission directing that person to the commission’s Web site for information on state laws, commission rules and directions on how to fill out campaign reports.

But the lion’s share of credit card charges are still reported merely as payments to American Express, Discover, MasterCard and Visa, among others.

“Just showing Visa or MasterCard for tens of thousands of dollars doesn’t show you whether the money was spent on political advertising,” said Ethics Commission Vice Chairman Tom Harrison.  “It’s kind of like hiding behind the credit card.”